note - what is "BIOS INT 13h AX=4C00h" ? mentioned in ISOLINUX wiki

This is a translation of my page ノート 「BIOS INT 13h AX=4C00h」について - SYSLINUX、ElToritoBoot 関連の話題

---
From SYSLINUX wiki - Can I boot other operating systems with ISOLINUX?

Starting in version 1.65, ISOLINUX supports booting disk images of other operating systems. However, this feature depends on BIOS functionality which is apparently broken in a very large number of BIOSes.
...
please complain to your vendor and indicate that "BIOS INT 13h AX=4C00h fails". Note that you can use MEMDISK as a recommended alternative;

What "BIOS INT 13h AX=4C00h" mean?

The answer is "ElToritoBoot".
El torito boot is used for bootable DVD, etc.

---
syslinux/syslinux.git - path: root/memdisk/memdisk.inc

Int13Funcs
...
%if ELTORITO ; EDD El Torito Functions
; ELTORITO _must_ also have EDD
dw ElToritoEmulate ; 4Ah - Initiate Disk Emulation
dw ElToritoTerminate ; 4Bh - Terminate Disk Emulation
dw ElToritoBoot ; 4Ch - Initiate Disk Emu. and Reboot
dw ElToritoCatalog ; 4Dh - Return Boot Catalog
%endif ; ELTORITO